The Plural of Anecdote Is Not Data

Dear Quote Investigator: Each datum in a collection of data may be considered a story. Yet, it is often difficult to make rigorous conclusions based on a motley collection of anecdotes. Scientific data should be collected in a methodical manner according to a well-specified protocol. This viewpoint is concisely stated as follows:

The plural of anecdote is not data.

Would you please explore the history of this statement?

Quote Investigator: The earliest strong match known to QI appeared in an article by Kenneth Kernaghan and P. K. Kuruvilla in the journal “Canadian Public Administration” in 1982. Emphasis added to excerpts by QI: 1

In that the plural of the word anecdote is not data, it is difficult to provide hard information on selection problems.

The citation above is listed in the valuable reference “The Dictionary of Modern Proverbs” from Yale University Press.

Interestingly, the same expression without the negation is also an adage which has been explored by QI in a separate article here.

Below are additional selected citations in chronological order.

In 1967 economist and future Nobel laureate Paul A. Samuelson made a thematically similar observation in the pages of “Newsweek” magazine: 2

Anecdotes do not constitute social science. They must be documented by some notion of the frequency of their occurrence.

In 1982 Kenneth Kernaghan and P.K. Kuruvilla published an article with the saying as noted previously.

In 1988 Professor of Psychology and primatologist Irwin S. Bernstein writing in the journal “Behavioral and Brain Sciences” employed the saying: 3

One cannot do science with independent variables held constant or allowed to vary without measurement. Astronomy did not progress by only observing dependent variables. It was the measurement and correlation of both that led to progress. Relying on anecdotes, no matter how numerous, fails to specify any value of the independent variable, or the intentional state of an animal. The plural of “anecdote” is not “data.”

In 1989 a variant expression appeared in “The Christian Century” with an anonymous attribution: 4

Someone once made the wise point that research is not the plural of anecdote. But surely the only way to begin to understand another culture is to listen to the stories of people who live in it.

In 1995 “The Justice System Journal” published a book review by Edith Greene that included the remark: 5

I have no doubt that some juries make egregious errors, that some jurors are hopelessly prejudiced, and that some verdicts are indeed outrageous. But this collection of anecdotes, and Adler’s take on them, does not convince me that the jury system is in trouble. The plural of anecdote is not data.

Also in 1995 Sally Scully of San Francisco State University employed the adage within an article in the “Journal of Social History”: 6

While the plural of anecdote is not data, gingerly reconstructed biography catches the individual who otherwise falls through the statistical grid.

In 1996 “Monographs of the Society for Research in Child Development” published an article titled “What Young Chimpanzees Know about Seeing” which included the saying with a pointer to the 1988 article by Irwin S. Bernstein: 7

Third, with regard to deception, interpretation is an especially difficult issue, as almost all the reported observations are anecdotes (for the view that “the plural of anecdote is not data,” see Bernstein, 1988).

In conclusion, the first known instance appeared in a 1982 journal article by Kenneth Kernaghan and P. K. Kuruvilla. These authors may have crafted the adage, but the ascription is provisional; future research may uncover earlier examples. A closely related saying without negation: “The plural of anecdote is data” appeared a couple years earlier in 1980. The two antithetical remarks may have circulated and evolved together.

(Great thanks to szescstopni, Joel S. Freund, Barry Ritholtz, and Carl V. Phillips whose inquiries led QI to formulate this question and perform this exploration. Many thanks to Bonnie Taylor-Blake who gained access to the 1988 citation. Additional thanks to Jeff Braemer who asked about the positive version of the adage. Special thanks to Fred R. Shapiro, Charles Clay Doyle, and Wolfgang Mieder for their pioneering research. Also, thanks to discussants Barry Popik, Sam Clements, John Baker, Aaron Dinkin, and Mark A. Mandel.)

Update History: On January 24, 2018 the 1988 citation was added to the article.

Notes:

2012, The Dictionary of Modern Proverbs, Compiled by Charles Clay Doyle, Wolfgang Mieder, and Fred R. Shapiro, Quote Page 202, Yale University Press, New Haven. (Verified in Dictionary of Modern Proverbs) (Citation for adage – not yet verified by QI: 1982 Kenneth Kernaghan, “Merit and Motivation: Public Personnel Management in Canada,” Canadian Public Administration 25: 703; text is visible in a snippet from the Google Books database) ↩

1996, Monographs of the Society for Research in Child Development, Volume 61, Number 3, Article: What Young Chimpanzees Know about Seeing, Authors: Daniel J. Povinelli, Timothy J. Eddy, R. Peter Hobson and Michael Tomasello, Quote Page 165, Published by: Wiley on behalf of the Society for Research in Child Development. (JSTOR) link↩